Car is an 82 Fb with a Jspec S-5 swap, mods are full 3inch exhaust and d.p., with 2.5 tid, cone filter, r.b. fcd, rc 750 in the secondaries, cleaned 550, walboro 255 and aeromotive fpr with rising rate, it has a SE gas tank and lines as well, Heavy port on the w.g, also running 4.44 in the rear, Stock jpsec ecu. No emissions what so ever. t.b mod and msd 6al on the leading.
OK so the problem is runs perfect 95% of the time, when doing hard pulls in 3rd or 4th, it will instantly hit 5 psi, then creep up to 7psi still pulling hard. then instantly hits 10 psi and has absolutely no power. It pulls harder at 5 psi then it does at 10 psi. You can feel it instantly go flat. So I immediately pull my foot out of it. Putting bigger injectors in the secondaries helped some and as well as cleaning the primaries, When I first got it running it was an absolute bear at 10 psi now it has been nuertered. any ideas ? I hooked up a fuel line to the port on the fpr and watch the psi on a gauge in the cab, ya I know real safe, no issues with fuel pressure under boost, I have it set at 40 psi at idle and it goes up to 50 psi fairly quick under boost.
I have a feeling it might be the ecu, its a 374. came directly from Japan via E bay.. Thanks for looking.

 

I am getting the same thing. I have come down to fuel or ECU. I am getting ready to bet the ranch on the ECU FWIW to you.

 

First of all, you need to confirm if you're running rich or lean?

To me, it sounds like it's getting too much fuel.

You base pressure at idle is about 5psi too high.
Stock is 35 - 37psi at idle; 40psi at "0".

As for the FPR, is it truly a "rising rate"?
"Rising rate" implies a ratio larger than 1:1.
1:1 is technically called a "boost dependent" FPR.
If it's a true rising rate (i.e. 5:1, 7:1, etc.), then I can guarantee you it's way too much fuel.

The larger secondaries with no way of leaning them down dumps too much fuel into the engine, IME.

Ever looked at your spark plugs?
I bet they are black...


-Ted

 

Thanks Ted,
I will turn the fuel pressure down to 35 psi today. The FPR is Aeromotive 13109 which the catalog says rises at a 1:1 ratio. So your right about that, I have checked the plug in the past and they were ash to black, I think the msd and blaster coils might be masking the fact i am using to much fuel.

I just picked up a used Super AFC with the four buttons, first gen i think. I was waiting to install and dyno tune until i did a small fmic.
Should I just do the afc now? or wait until i do the fmic. Also what afr should I have them tune for?
I am running a autometer sport comp afr narrow band and it pretty much is in the middle to high side of the rich area. I know they are not much good except for a general idea. Thanks for your help. This is my first fuel injection and turbo project, figured i get all the hair pulling over at one time.

 

Turned down the fuel pressure to 36 psi, seems like it might have helped a little. Definately not worse by any means. How black and sooty will plug be if it is running extra rich. Ideally what should they look like.
Thanks